AVS 45th International Symposium
    Vacuum Metallurgy Division Monday Sessions
       Session VM+TF-MoM

Paper VM+TF-MoM5
Effects of Coil dc Potential on Ion Energy Distribution Measured by an Energy-resolved Mass Spectrometer in Ionized Physical Vapor Deposition

Monday, November 2, 1998, 9:40 am, Room 328

Session: Ionized-PVD: Processes, Properties, and Applications
Presenter: E. Kusano, Kanazawa Institute of Technology, Japan
Authors: E. Kusano, Kanazawa Institute of Technology, Japan
T. Kobayashi, Kanazawa Institute of Technology, Japan
N. Kikuchi, Kanazawa Institute of Technology, Japan
K. Fukushima, Kanazawa Institute of Technology, Japan
T. Saitoh, Kanazawa Institute of Technology, Japan
S. Saiki, Kanazawa Institute of Technology, Japan
H. Nanto, Kanazawa Institute of Technology, Japan
A. Kinbara, Kanazawa Institute of Technology, Japan
Correspondent: Click to Email
In ionized physical vapor deposition, ion energy distribution is crucial to obtain films with desired properties. The energy distribution is supposed to be affected by the plasma potential that relates to the coil dc potential induced by an applied rf power. In this study, ion energy distribution of ionized Ti particles and Ar discharge gas has been measured by an energy-resolved mass spectrometer for various coil dc potential. The sputtering cathode used in the experiment was a conventional magnetron sputtering source with a Ti target (55mm@phi@). The cathode was coupled with an rf coil (60mm@phi@, made of Cu) generating an additional plasma in the region between the target and the substrate. The mass spectrometer was a Balzers PPM421 plasma monitor. The orifice to the ion optics was 0.1mm@phi@ and electrically grounded. The coil dc potential was controlled by changing the resistance of the resistor in the LCR circuit connecting the coil to the ground. The results showed that the energy of Ti@super +@ and Ar@super +@ was enhanced from a few eV to more than 100eV as a coil rf power increased from 0 to 200W for a constant cathode dc current. By changing the resistance of the LCR circuit, the peak of the energy spectra shifted from about 160eV for the resistance of 0@OMEGA@(the coil was grounded) to about 100eV for the resistance of 1k@OMEGA@. In addition, it was found that the total energy of Ti@super +@ or Ar@super +@ arriving to the spectrometer increased as the resistance decreased. The results suggest that the coil potential to the ground affect the plasma potential and thus the energy distribution of ions arriving to the electrically grounded substrate through the plasma sheath.